…python into bug/ipc

…ded tests for large payloads and partial chunks.

…d logic

…ter handling

…d subprocess-based test for framed JSON-RPC communication

… using `anyio.to_thread.run_sync`.

…stdout` buffer, ensuring isolated binary protocol handling on `stdout`.

…sistency in test file naming.

…Client`, directly using `sys.stdout.buffer` for simplicity and consistency.